VNC4FREE is a Windows x64 desktop viewer for connecting to computers that already run a VNC server. It supports standard RFB 3.3, 3.7 and 3.8 sessions, including classic VNC password authentication, and can reach plain TCP, TLS, WebSocket and Secure WebSocket endpoints.
Saved connection profiles, groups, favorites and search live in an address book, with up to 16 sessions in tabs, Send keys shortcuts, view-only mode, clipboard transfer, fullscreen and PNG screenshot capture.
README
VNC4FREE for Windows
A free Windows x64 desktop viewer for connecting to computers that already run a VNC server.
Run VNC4FREE Setup - Program Files.exe and approve the Windows administrator prompt. The default destination is C:\Program Files (x86)\VNC4FREE. You can choose another folder and optionally add a desktop shortcut for all users.
Open VNC4FREE from the Start menu.
In Quick connect, enter the server address and select Connect. If the server requests credentials, enter them in the dialog. For TLS or a saved connection, choose New connection and select the connection type.
To remove the app, open Settings → Apps → Installed apps and choose Uninstall for VNC4FREE. Saved connections and preferences are kept.
For the portable ZIP, extract the complete VNC4FREE folder and open VNC4FREE.exe from it. Keep the executable and the files beside it together.
Example
What it opens
workstation.local
VNC on TCP port 5900
workstation.local:5901 or workstation.local:1
VNC on TCP port 5901
workstation.local::90
Explicit TCP port 90
[2001:db8::10]:5900
VNC over IPv6
wss://gateway.example.org/websockify
Secure WebSocket endpoint carrying VNC
ws://127.0.0.1:6080/websockify
WebSocket endpoint carrying VNC
The installer and portable build are unsigned. Windows may show a SmartScreen prompt.
Use the viewer
Save named profiles, add groups and favorites, search the address book, and reopen recently used saved connections. Settings imports and exports the viewer's JSON address book.
After connecting successfully to an unsaved server, choose Save connection or Not now. Select Never show again to stop the prompt. Open Recent to save previously connected servers or turn the prompt back on in Settings.
Keep up to 16 sessions in tabs. Pick Fit to window or Actual size. Request remote resize is a per-profile option for servers that support client-initiated resizing.
Use Send keys for Ctrl+Alt+Delete, Alt+Tab, Alt+F4, the Windows key, and Escape. View only suppresses keyboard and pointer input.
Use Clipboard to send local text or explicitly copy text received from the remote server. The available character set depends on the server's clipboard protocol. Clipboard commands can be disabled per profile.
Save a PNG of the remote framebuffer with the screenshot button. F11 toggles fullscreen and F8 opens session commands. Ctrl+L focuses Quick connect from the address book.
Reconnect manually from an ended session. By default, the viewer retries interrupted sessions up to three times and prompts again if the server requests credentials.
Adjust image quality, compression, shared access, and startup display mode in a saved profile. The server chooses which advertised encoding to use.
Connection security and compatibility
The viewer supports standard RFB 3.3, 3.7, and 3.8 sessions, including classic VNC password authentication. The bundled noVNC engine handles the encoding and authentication negotiation. Compatibility depends on which security modes and extensions the server offers.
Direct VNC (TCP) and WebSocket (WS) do not encrypt the transport. Use them on a trusted network or inside an encrypted tunnel. Classic VNC password authentication also has a legacy eight-byte password limit. With Windows OpenSSH and an existing SSH server, an example local tunnel is ssh -N -L 5905:127.0.0.1:5900 user@remote-host. Keep that terminal open and connect to 127.0.0.1:5905.
Direct VNC over TLS expects a TLS wrapper such as stunnel at the selected endpoint, with standard VNC inside it. It validates the certificate chain and hostname against trusted roots, including the Windows certificate store. Secure WebSocket (WSS) expects a WebSocket gateway such as websockify or a VNC server with native WebSocket support. The viewer has no certificate bypass. Native VeNCrypt TLS/X.509 negotiation, proprietary vendor encryption, RealVNC cloud sign-in, vendor-specific file transfer, remote printing, chat, and audio are outside this build.
VNC login credentials are requested in memory and omitted from the address book. Saved WebSocket URLs are stored as entered, so treat a URL containing a private gateway token and any address book that contains it as sensitive. Settings are stored under %APPDATA%\VNC4FREE.
On first use, VNC4FREE can read the previous VNC Viewer address book and preferences. New changes go to the VNC4FREE settings folder.
Source and verification
The source archive contains the application, locked dependencies, Windows packaging script, protocol fixture, and desktop tests. See TESTING.md for commands and coverage. See THIRD-PARTY.md for the sources that informed the feature set and the licenses for the bundled components.